Bio Study Guide Unit 7: Interdependent Relationships in Ecosystems

Comprehensive flashcards covering the key terms and concepts from Chapters 34, 36, and 37 regarding interdependent relationships in ecosystems.

What is the primary difference between biotic and abiotic components of an ecosystem?

Biotic components consist of all the living organisms in an area, while abiotic components are the environment's non-living chemical and physical factors.

How is a population defined in population ecology?

a group of individuals of a single species that occupy the same general area.

What is population ecology?

the study of how and why populations change over time.

What does the term population density refer to?

the number of individuals of a species per unit area or volume.

How is the exponential growth model characterized?

The exponential growth model describes the expansion of a population in an idealized, unlimited environment.

What is the defining characteristic of the logistic growth model?

The logistic growth model describes population growth that is slowed by limiting factors as the population size increases.

What is meant by the carrying capacity of an ecosystem?

the maximum population size that a particular environment can sustain.

What are density-dependent factors in population regulation?

limiting factors whose intensity is related to population density.

What are density-independent factors?

limiting factors whose intensity is unrelated to population density.

How is a biological community defined?

an assemblage of all the populations of organisms living close enough together for potential interaction.

What is interspecific competition?

occur when populations of two different species compete for the same limited resource.

What is mutualism in a community structure?

an interspecific interaction in which both populations benefit.

Define predation.

an interaction where one species, the predator, kills and eats another, the prey.

What is herbivory?

the consumption of plant parts or algae by an animal.

How is parasitism characterized?

an interaction where one organism, the parasite, lives on or in a host from which it obtains nourishment.

What is a food chain?

A a sequence of food transfer up the trophic levels.

What defines a food web?

a network of interconnecting food chains.

What is a keystone species?

a species whose impact on its community is much larger than its abundance or total biomass would indicate.

How does energy flow through an ecosystem?

by entering as sunlight, being converted to chemical energy by producers, and then being passed to consumers.

Why are there typically more producers than consumers in an ecosystem?

energy is lost as heat at each trophic level, meaning less energy is available to support organisms at higher levels.

Why is eating meat considered a "great luxury" in terms of energy flow?

it takes significantly more producer energy to support a person eating as a secondary consumer than as a primary consumer.

Definition: Biomass

the total mass of living organic matter in an ecosystem.

What is the role of a decomposer?

such as prokaryotes and fungi secrete enzymes that digest molecules in organic material and convert them to inorganic forms.

What is detritus?

dead organic matter.

Define a scavenger.

an animal that consumes the carcasses of other animals.

What is an invasive species?

a non-native species that has established itself in a new location and often causes environmental or economic damage.

What does species diversity represent?

the variety of species that make up a community.

What is a biome?

a major type of ecological association that occupies a broad geographic region of land or water.

Define the biosphere.

the entire portion of Earth inhabited by life; the sum of all the planet's ecosystems.

What is a limiting factor?

an environmental factor that restricts population growth.